Greece (Greek: Ελλάδα, romanized: Elláda, [eˈlaða]), officially the Hellenic Republic, is a country located in Southeastern Europe. Its population is approximately 10.7 million as of 2018, Athens is its largest and capital city, followed by Thessaloniki. Situated on the southern tip of the Balkans, Greece is located at the crossroads of Europe, Asia, and Africa. It shares land borders with Albania to the northwest, North Macedonia and Bulgaria to the north, and Turkey to the northeast. The Aegean Sea lies to the east of the mainland, the Ionian Sea to the west, the Cretan Sea and the Mediterranean Sea to the south. Greece has the longest coastline on the Mediterranean Basin and the 11th longest coastline in the world at 13,676 km (8,498 mi) in length, featuring many islands, of which 227 are inhabited. Eighty percent of Greece is mountainous, with Mount Olympus being the highest peak at 2,918 metres (9,573 ft). The country consists of nine traditional geographic regions: Macedonia, Central Greece, the Peloponnese, Thessaly, Epirus, the Aegean Islands (including the Dodecanese and Cyclades), Thrace, Crete, and the Ionian Islands.

Greece is considered the cradle of Western civilization, being the birthplace of democracy, Western philosophy, Western literature, historiography, political science, major scientific and mathematical principles, theatre and the Olympic Games. From the eighth century BC, the Greeks were organised into various independent city-states, known as poleis (singular polis), which spanned the Mediterranean and the Black Sea. Philip II of Macedon united most of present-day Greece in the fourth century BC, with his son Alexander the Great rapidly conquering much of the ancient world, from the eastern Mediterranean to India. The subsequent Hellenistic period saw the height of Greek culture and influence in antiquity.